GB1578646A - Narrow gauge tufting apparatus - Google Patents

Description

(54) NARROW GAUGE TUFTING APPARATUS (71) We, TUFTCO CORPORATION of 2318 Holtzclaw Avenue, Chattanooga, Tennessee 37404, U.S.A., a Company organised and existing under the Laws of Tennessee U.S.A., do hereby dec;are the invention for which we pray that a Patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a tufting machine, especially but not exclusively a narrow gauge cut pile tufting machine.

In multiple needle tufting machines having needle gauges as small as 1/lOth inch in a straight, single row of needles, the needles are so close together that their penetration of the cloth weakens the fabric and tears the fabric backing. Furthermore, this severely restricts the size of needles that can be used and therefore restricts also the size of yarn which can be tufted.

Previous attempts to employ staggered needles on a 1/lOth inch gauge in a cut pile tufting machine have not permitted sufficient room between the needles for the hooks, knives and yarns to pass, so long as the loopers and knives are of conventional thicknesses.

Heretofore, it has been believed that the employment of loopers and knives of lesser thickness would render the loopers and knives too weak, or at best too flexible, for satisfactorily carrying out their functions of rapidly holding and cutting the loops formed by the rapidly penetrating needles.

A suggested solution to one of the above problems is set forth in U.S. Patent No.

4,003,321 for "CUT PILE APPARATUS FOR STAGGERED NEEDLE TUFTING MACHINE". In the Patent, the needles are staggered, but all of the hooks have bills of different lengths, so that the hook throats may be mounted in alignment, and the bills of the hooks will cross their corresponding needles by virtue of their lengths varying correspondingly to the longitudinal spacing between the rows of staggered needles.

Accordingly, the knives in such a tufting machine may also be aligned, so that none of the knives has to move between any of the needles. Therefore, the knives do not clutter up the spacing between the needles, even staggered needles. However, even the needle gauge in such a staggered needle arrangement is limited by the thickness or width of the bills of the corresponding hooks.

It is an object of at least one aspect of this invention to provide a successfully operative tufting machine having a needle gauge at least as or more narrow than conventional needle gauges, in the order of 1/lOth inch.

In the tufting machine made in accordance with this invention, the needles are staggered and, when applied to a cut pile tufting machine, the hook and knife arrangement are the same as those in the U.S. Patent 4,003,32', that is the bills of the hooks vary in length to co-operate with their respective staggered needles, while the throats of all the hooks remain in substantial transverse alignment.According to this invention there is provided a tufting machine having means for supporting a base fabric for longitudinal movement in a feeding direction through said machine, including a narrow gauge tufting apparatus comprising: (a) a first row of reciprocable uniformly spaced needles for introducing yarn through the base fabric to form first loops, (b) a second row of reciprocable uniformly spaced needles for introducing yarn through the base fabric to form second loops, (c) said second row of needles being staggered relative to said first row of needles on a uniform gauge less than the transverse dimension of each of said uniformly spaced needles, said rows being longitudinally spaced apart a predetermined distance substantially greater than said gauge, (d) a first hook for each needle in said first row, each first hook having a throat and a bill projecting from said throat, (e) a second hook for each needle in said second row, each second hook having a throat and a bill projecting from the throat of said second hook, (f) each bill of said first and second hooks having a uniform narrow width substantially less than said gauge and being made from a material permitting each bill to flex transversely as said bill engages its corresponding needle, (g) a reciprocable hook bar means extending transversely of said feeding direction adjacent said fabric supporting means, each hook being fixed to said hook bar means so that each first hook co-operates with a corresponding needle in said first row to form a first loop and each second hook co-operates with a corresponding needle in said second row, to form a second loop.

The width or thickness of each looper or cut pile hook may conveniently be reduced to approximately 1/2 of the width of a conventional looper. Such reduction in width not only provides more space between the loopers and the needles, thereby permitting a narrower needle gauge, but also permits the hooks to be more flexible. Because of the increased flexibility of the hooks, each hook may be set closer to a line extending in the fabric feed direction and extending through the centre line of the corresponding needle. In other words, the more flexible loopers may be offset a lesser distance from the centre line of the needle than a conventional, thicker looper, to improve the capability of the more flexible looper to pick up a yam loop from its corresponding needle.

Furthermore, a typical needle having a flat spot normally rotated to about 10 with respect to the longitudinal feeding axis, may be rotated even further, as desired, tilting the scarf of the needle which is on the same side of the needle as the spot, to a position only slightly offset from the longitudinal line extending through the centre line of the needle and in alignment with the barbed end of the cut pile hook. Such an arrangement between the increased rotation of the needle and the position of the looper close to the centre line of the needle permits a greater camming action as the looper strikes the scarf of the needle so that the looper has an improved capability of picking up the yarns carried by the corresponding needle.For example, a filament yarn, or an untwisted yarn, which is more difficult to pick up by a conventional looper, is readily picked up by the flexible looper employed in this invention.

Although it had been feared that the employment of a more flexible looper would create unstable and erratic performance by the cut pile forming elements, nevertheless the opposite has been found to be true. The flexing of the looper is controlled by its en gagement with the scarf and the spot of the needle, so that the lateral deviation of the looper, albeit greater, nevertheless is con sistent, and results in a better pickup function of the yarns carried by the needles.

Another important function performed by the more flexible looper or hook is that the hook can flex to partially conform to the pitch angle (as herein defined) of the knife. In a machine with conventional hooks and knives, the pitch angle of each knife, which is usually about 4", places the tip of the knife under neath the hook where it is actually in inter ference. In order to pass the hook cutting edge as the knife closes, the knife first must cam itself outward on the normally stiff hook.

When the knife edge first contacts the cutting edge of the hook there is usually a hesitation.

Then, the knife springs away enough to pass the hook edge, causing a gap to wear in the cutting edge of the hook.

With the use of flexible hooks as described, the cutting action is smoother, because some of the flexing is in the hook instead of all of the flexing being in the knife. The pres sure between these two parts is reduced so that the interaction is less abrupt, the wcar life is increased, and a cleaner cut is produced.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, wherein : - Figure 1 is a fragmentary sectional eleva tion of a portion of the tufting machine according to an embodiment of the invention, disclosing the cut pile apparatus in a noncutting position; Figure 2 is a fragmentary front end elevation of the looper and knife assembly disclosed in Figure 1; Figure 3 is an enlarged, fragmentary section taken along the line 3-3 of Figure 1, with portions broken away, and the yams removed; Figure 4 is an enlarged, fragmentary section taken along the line 44 of Figure 1; Figure 5 is a fragmentary sectional elevation, similar to Figure 1, disclosing the cut pile apparatus in a cutting position; ; Figure 6 is an enlarged, fragmentary section taken along the line 6-6 of Figure 5, with some of the yarns removed; and Figure 7 is a view similar to Figure 6, showing the flexible loopers picking up the yarns from the needles.

Referring now to the drawings in more detail, Figure 1 discloses a typical needle bar 10 supporting a plurality of needles 11 in a first or rear transverse row, and a plurality of needles 12 in a second or front transverse row spaced longitudinally forward of the first row of needles 11. The needle bar 10 is adapted to move reciprocally between its lower position disclosed in Figures 1 and 2, to an upper position, not shown, in which the needles 11 and 12 are above the base fabric 14. The needle bar 10 is driven by conventional means, not shown.

As best disclosed in Figure 3, the needles 11 in the first row and the needles 12 in the second row are alternately staggered trans versely of the tufting machine.

The base fabric 14 is supported upon a needle plate 15 for movement longitudinally from front-to-rear in a feeding direction, indicated by the arrow in Figures 1 and 5, through the tufting machine. Each needle 11 carries a yarn 16 and each needle 12 carries a yarn 17 through the base fabric 14 upon each stroke of the needle bar 10.

The cut pile apparatus includes a plurality of first cut pile hooks 19 and a plurality of second cut pile hooks 20, all of which cut pile hooks 19 and 20 are fixedly supported upon a hook bar 21 for reciprocal movement, by conventional means, not shown.

Each cut pile hook 19 of the first set includes an elongated shank 23 adapted to fit in a corresponding slot 24 in rhe hook bar ?.1. The first cut pile hook also includes a vertically disposed throat 25 from which projects in the direction opposite to the fabric feeding direction, a bill 26 of predetermined length. The point 27 of the bill 26 is barbed or downturned, in the conventional manner for cut pile hooks.

Each cut pile hook 20 of the second set is made substantially identical to the construction of a first cut pile hook 19, having a shank, not shown, identical to the shank 23, and a throat 29 identical to the throat 25.

However, the bill 30 of each cut pile hook 20 of the second set is longer than the bill 26 of a first cut pile hook 19. The difference in the lengths of the bills 30 and 26 is preferably equa! to the longitudinal spacing between the transverse rows of needles 11 and 12. Each bill 30 may be provided with the same downturned or barbed end 31, if desired.

Thus, by inserting the shanks of alternating first and second cut pile hooks 19 and 20 in the uniformly spaced and sized slots 24 in the same hook bar 21, the throats 25 and 29 of all the cut pile hooks 19 and 20 will be transversely aligned, as indicated in Figure 3. However, the bills 26 and 30 being of alternately different lengths, will project a corresponding amount across each alternately staggered needle 11 and 12, as best disclosed in Figure 3.

In a conventional cut pile tufting apparatus, and even in the cut pile tufting apparatus disclosed in the above U.S. Patent 4,003,321, the width of or thickness of the hooks 19 and 20 is of a conventional or standard size, which is about .055 or .060 inches. Such hooks have been used with needles whose overall diameters are approximately .120 or .125 inches. A typical fine or narrow needle gauge is approximately 1/8th inch or 5/32nds inch, even where the needles are staggered.

In the apparatus described the needles re main of conventional size, that is about .120 or .125 inches in overall diameter. However, the needle gauge has been reduced to .10, i.e.

less than the transversal dimension of each of said uniform needles, and the thickness or width of each of the loopers or hooks 19 and 20 has been reduced by about 1/2 to a hook thickness of .032 inches. The rows of needles 11 and 12 are spaced by a distance which is substantially greater than said gauge. The hooks 19 and 20 are made out of the same steel from which conventional hooks are made, but by virtue of their reduction in width, they are more flexible so that they more readily yield or flex, and are deviated laterally, preferably by at least twice their own width, when the barb of each of the hooks 19 and 20 engages its corresponding needle 11 and 12 for camming action along the side of the needle to pick up the respect- ive yarns 16 and 17.

By virtue of this greater flexibility in the hooks 19 and 20, they may be set laterally or transversely closer to the centre line of their corresponding needle, as indicated in Figure 6.

Since the more flexible hooks are located transversely closer to the centre line of each needle, each needle may be rotated or angularly arranged to bring the scarf 33 of the respective needle also closer transversely to the centre line of its respective needle, so that each scarf 33 is longitudinallly opposing the barbed end 27 and 31 of the respective looper 19 and 20.

Typically, the needle spot 34, which is the flat planar side surface of the needle, is disposed at approximately 10 to the longitudinal direction of fabric feed in a conventional cut pile tufting machine. In this aparatus the needle spot may if desired be rotated to an agle of less than 10 to the longitudinal direction of fabric feed in order to locate the scarf 33 in opposition to, and in longitudinal alignment with its corresponding looper 19 or 20. A preferred angular range of the needle spot to the fabric feed direction would be 5--20".

As illustrated in Figure 7, as each hook 19 and 20 crosses its respective needle 11 and 12, the scarf 33 and spot 34 of the needle cam the respective barbed end 27 and 31 of the corresponding hook laterally outward, but in tensioned engagement with the corresponding needle, causing the barbed end of each respective looper better to engage the respective yarns 16 and 17 and hold the respectively formed loops 36 and 37 thereon.

The cutting aparatus for this narrow gauge cut pile tufting machine includes a knife holder or knife block 40, having a shank 41 fitted within a corresponding recess in a knife bar 42.

The knife block 40 is arranged so that the knives 51-54 held thereby will be presented to the hooks 19-20 with a "pitch angle" and a "tension angle". The "pitch angle" as used herein and in the appended claims is the angle at which the shank 41 lies, assuming that the shank 41 lies in a horizontal plane, relative to a vertical plane extending in the direction of feed of the fabric through the machine.

The "tension angle" as used herein and in the appended claims, means the angle by which the knife block is rotated around the axis of the shank 41 from a vertical plane containing the axis of the shank 41.

The knife bar 42 is adapted to oscillate about its longitudinal or rocking axis in a con ventional manner. The knife block 40 includes an elongated web 43 terminating in a pair of flanges 44 and 45 disposed substantially at right angles to the web 43. The cross section of knife block 40 resembles an I-beam.

The opposed inner faces of the flanges 44 and 45 are cut to form opposed knife re cesses for channels or tracks 47, 48, 49 and 50. The tracks 47 and 48 are on one side of the web 43, while the tracks 49 and 50 are on the opposite side of the web 43. The spacing and sizes of the knife recesses 47, 48, 49 and 50 are such as to snugly but slidably receive longitudinally within the recesses the respective knives or knife blades 51, 52, 53 and 54.

In order to save as much space as possible and to bring the knives 51 54 as close as possible to conform to the narrow gauge of needles 11 and 12, the innermost recesses 47 and 48 on one side of the web 43 and the innermost recesses 49 and 50 on the opposite side of the web 43 may be formed so that one of their walls is flush with each face surface of the web 43, as best disclosed in Figure 4.

In order to secure the knives 51-54 within the knife block 40, a pair of headed bolts 55 and 56 are inserted through corresponding openings within the flange 45 of the knife block 40 so that the shanks 57 extend between the corresponding respective blades 51-52 and 53-54, and extend through mating openings in the opposite flange 44. The free ends of the bolts 55 and 56 are threaded to co-operate with threaded square nuts 59 and 60. The square nuts 59 and 60 are seated in a transverse recess 61 of the flange 44.

The bottom of the recess 61 extends depthwise into the flange 44 far enough to intercept the recesses 47 and 49. Thus, when the nuts 59 and 60 are tightened upon the respective bolts 55 and 56 to a sufficient degree, they actually engage the edges of the knives 51-54 to bind and hold the knives in their respective positions within the block 40. This binding effect is best disclosed in Figure 1 illustrating the nut 60 engaging the edge of the knife blade 54.

The shank 41, as best disclosed in Figure 2, is rotated within the knife bar 42, in a conventional manner, to dispose the knife block 40 at a predetermined tension angle between the respective blades 51-54 and the sides of the cut pile hooks 19 and 20. The typical tension angle would be 9 . Thus, as disclosed in Figures 1-4, the knife block 40 is set not only at a pitch angle of approximately 4" to the knife bar 42, but also at a tension angle of approximately 9" to hooks 19 and 20.

Because of the pitch angle, the knives, such as knives 51-54, would be aligned with each other in a line at an angle to the alingnment of the hooks and the needles. Therefore, in order to accomodate for this disalignment of the knives with the hooks, the knives 51 and 52, in alignment with each other, are staggered relative to the aligned knives 53 and 54 by an offset amount X, as disclosed in Figure 4. It is not felt that every knife has to be'offset with every adjacent knife because of the closeness of the gauge.

Accordingly, only every pair of knives 51-52 and 53-54 in each block 40 is offset from the other pair by the amount X.

Thus, the recesses 47 are aligned with each other, but are offset by the amount X from the recesses 49. Correspondingly, the recesses 48 are offset by the same amount X from the recesses 50 in the opposite flange 45. In this manner, substantial alignment of the knives 51-54 is preserved with the alignment of the hooks 19 and 20, as best disclosed in Figure 3.

It will thus be seen that in the knife block 40, the knives 51-54 may be spaced closer together to correspond with a narrow needle gauge, in the order of 1/lOth inch. It is possible to provide a knife block 40 having recesses offset at least in pairs for accomodating a multiple number of knife blades greater than four. However, the knife block 40 with its shank 41 is adapted to fit within corresponding holes having conventional spacing in a conventional knife bar.

Application No. 20173/79 (Serial No.

1,578,647) is divided out by this application.

The complete specification of said Application No. 20173/79 (Serial No. 1,578,647) described the same apparatus as described with reference to the drawings in this application.

WHAT WE CLAIM IS:- 1. A tufting machine having means for supporting a base fabric for longitudinal movement in a feeding direction through said

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (12)

**WARNING** start of CLMS field may overlap end of DESC **. cut pile tufting machine includes a knife holder or knife block 40, having a shank 41 fitted within a corresponding recess in a knife bar 42. The knife block 40 is arranged so that the knives 51-54 held thereby will be presented to the hooks 19-20 with a "pitch angle" and a "tension angle". The "pitch angle" as used herein and in the appended claims is the angle at which the shank 41 lies, assuming that the shank 41 lies in a horizontal plane, relative to a vertical plane extending in the direction of feed of the fabric through the machine. The "tension angle" as used herein and in the appended claims, means the angle by which the knife block is rotated around the axis of the shank 41 from a vertical plane containing the axis of the shank 41. The knife bar 42 is adapted to oscillate about its longitudinal or rocking axis in a con ventional manner. The knife block 40 includes an elongated web 43 terminating in a pair of flanges 44 and 45 disposed substantially at right angles to the web 43. The cross section of knife block 40 resembles an I-beam. The opposed inner faces of the flanges 44 and 45 are cut to form opposed knife re cesses for channels or tracks 47, 48, 49 and 50. The tracks 47 and 48 are on one side of the web 43, while the tracks 49 and 50 are on the opposite side of the web 43. The spacing and sizes of the knife recesses 47, 48, 49 and 50 are such as to snugly but slidably receive longitudinally within the recesses the respective knives or knife blades 51, 52, 53 and 54. In order to save as much space as possible and to bring the knives 51 54 as close as possible to conform to the narrow gauge of needles 11 and 12, the innermost recesses 47 and 48 on one side of the web 43 and the innermost recesses 49 and 50 on the opposite side of the web 43 may be formed so that one of their walls is flush with each face surface of the web 43, as best disclosed in Figure 4. In order to secure the knives 51-54 within the knife block 40, a pair of headed bolts 55 and 56 are inserted through corresponding openings within the flange 45 of the knife block 40 so that the shanks 57 extend between the corresponding respective blades 51-52 and 53-54, and extend through mating openings in the opposite flange 44. The free ends of the bolts 55 and 56 are threaded to co-operate with threaded square nuts 59 and 60. The square nuts 59 and 60 are seated in a transverse recess 61 of the flange 44. The bottom of the recess 61 extends depthwise into the flange 44 far enough to intercept the recesses 47 and 49. Thus, when the nuts 59 and 60 are tightened upon the respective bolts 55 and 56 to a sufficient degree, they actually engage the edges of the knives 51-54 to bind and hold the knives in their respective positions within the block 40. This binding effect is best disclosed in Figure 1 illustrating the nut 60 engaging the edge of the knife blade 54. The shank 41, as best disclosed in Figure 2, is rotated within the knife bar 42, in a conventional manner, to dispose the knife block 40 at a predetermined tension angle between the respective blades 51-54 and the sides of the cut pile hooks 19 and 20. The typical tension angle would be 9 . Thus, as disclosed in Figures 1-4, the knife block 40 is set not only at a pitch angle of approximately 4" to the knife bar 42, but also at a tension angle of approximately 9" to hooks 19 and 20. Because of the pitch angle, the knives, such as knives 51-54, would be aligned with each other in a line at an angle to the alingnment of the hooks and the needles. Therefore, in order to accomodate for this disalignment of the knives with the hooks, the knives 51 and 52, in alignment with each other, are staggered relative to the aligned knives 53 and 54 by an offset amount X, as disclosed in Figure 4. It is not felt that every knife has to be'offset with every adjacent knife because of the closeness of the gauge. Accordingly, only every pair of knives 51-52 and 53-54 in each block 40 is offset from the other pair by the amount X. Thus, the recesses 47 are aligned with each other, but are offset by the amount X from the recesses 49. Correspondingly, the recesses 48 are offset by the same amount X from the recesses 50 in the opposite flange 45. In this manner, substantial alignment of the knives 51-54 is preserved with the alignment of the hooks 19 and 20, as best disclosed in Figure 3. It will thus be seen that in the knife block 40, the knives 51-54 may be spaced closer together to correspond with a narrow needle gauge, in the order of 1/lOth inch. It is possible to provide a knife block 40 having recesses offset at least in pairs for accomodating a multiple number of knife blades greater than four. However, the knife block 40 with its shank 41 is adapted to fit within corresponding holes having conventional spacing in a conventional knife bar. Application No. 20173/79 (Serial No.

1,578,647) is divided out by this application.

The complete specification of said Application No. 20173/79 (Serial No. 1,578,647) described the same apparatus as described with reference to the drawings in this application.

WHAT WE CLAIM IS:- 1. A tufting machine having means for supporting a base fabric for longitudinal movement in a feeding direction through said

machine, including a narrow gauge tufting apparatus comprising: (a) a first row of reciprocable uniformly spaced needles for introducing yarn through the base fabric to form first loops, (b) a second row of reciprocable uniformly spaced needles for introducing yarn through the base fabric form second loops.

(c) said second row of needles being staggered relative to said first row of needles on a uniform gauge less than the transverse dimension of each of said uniformly spaced needles, said rows being longitudinally spaced apart a predetermined distance substantially greater than said gauge, (d) a first hook for each needle in said first row, each first hook having a throat and a bill projecting from said throat, (e) a second hook for each needle in said second row, each second hook having a throat and a bill projecting from the throat of said second hook, (f) each bill of said first and second hooks having z uniform narrow width substantially less than said gauge and being made from a material permitting each bill to flex transversely as said bill engages its corresponding needle, (g) a reciprocable hook bar means extending transversely of said feeding direction adjacent said fabric supporting means, each hook being fixed to said hook bar means so that each first hook co-operates with a corresponding needle in said first row to form a first loop and each second hook co-operates with a corresponding needle in said second row to form a second loop.

2. A tufting machine according to Claim 1, in which each of said hooks is a cut pile hook, and the machine further comprising a knife for each of said first and second cut pile hooks, knife supporting means supporting each of said knives for reciprocable co-operative movement with a corresponding hook to form first and second transverse rows of cut pile tufts.

3. A tufting machine according to Claim 2, in which each of said bills is adapted to flex transversely away from its corresponding knife as said knife co-operates with said corresponding bill to cut a pm loop carried by said bill.

4. A tufting machine according to Claim 2 or 3, in which each of said knives is mounted so as to lie at a predetermined pitch angle in said knife supporting means, and each of said bills has a cutting edge adapted to co-operate with the corresponding pitched knife for cutting the yarn loop carried by said bill.

5. A tufting machine according to Claims 2, 3 or 4, in which each of said knives is mounted on the opposite sides of its corresponding bill from the side of the bill that engages its corresponding needles, said bill being adapted to flex toward its corresponding knife when said bill engages its corresponding needle.

6. A tufting machine according to any of Claims 2 to 5, in which the throats of all said hooks are transversely aligned, the bills projecting from the throats of said first cut pile hooks being of a predetermined length, the bills projecting from the throats of said second cut pile hooks being of a length different from the length of the bills of said first cut pile hooks by an amount substantially equal to the longitudinal spacing between said first and second transverse rows of needles, and all said knives being in substantial transverse alignment parallel to the alignment of the throats of said bills.

7. A tufting machine according to any of Claims 2 to 6, in which said knife-supporting means comprises an oscillatory knife bar and at least one knife block, the or each of said knife blocks being flexed to said knife bar at a predetermined pitch angle, and means in the or each of the said knife blocks receiving a plurality of said knives in staggered rela tionships in said knife block and substantially in parallel alignment with the longitudinal axis of said knife bar.

8. A tufting machine according to Claim 7, in which the means for receiving said knives in the or each knife block comprise pairs of opposed aligned recesses for slidably receiving the longitudinal edges of each of said knives at least some of said pairs of recesses being staggered relative to another pair of recesses in the or each knife block.

9. A tufting machine according to any pre ceding claim, in which each of said needles has a flattened side including a needle spot terminating in a scarf, each of said needles being disposed at a uniform angle between said needle spot and said corresponding hook of approximately 5--20".

10. A tufting machine according to any preceding claim, in which each of said needles has a flattened side surface including a needle spot terminating in a scarf opposing said corresponding hook, the angle between said needle spot and said feeding direction being such that said scarf is only offset slightly from a longitudinal line extending through the centre of said needle.

11. A tufting machine according to any pre ceding claim, in which each of said bills is adapted to flex a transverse distance from the longitudinal normal axis of said bill at least twice as great as the width of said bill.

12. A tufting machine substantially as here inbefore described with reference to the accompanying drawings.